b'TECHNICAL TECHNICAL done, will fail. The lack of move-is sponsored by ment joints gives the tile assembly noroomtoexpand,causingthe tile to pop up or tent, most times in the middle of the fl oor. You must allow for this movement in all resi-dentialandcommercialprojects. Movement joints are not optionalthey are required.ARDEX X 4 LFT - Large Format Tile and Stone Mortar What the TCNA Handbook says ARDEXX4istheeverydayabout movement jointsgotomortarforlargeformatThe2020editionoftheTCNAtileandstone.ItissuitableforHandbook EJ171 Movement Joint setting most types of tile includingGuidelinesforCeramic,Glass mosaicsandnaturalstoneoverandStoneclearlystates:The commoninteriorsurfacesinclud- designprofessionalorengineer ingexteriorgradeplywood,asshallshowthespecifi clocations well as over exterior concrete orand details of movement joints on masonry surfaces. It can also beproject drawings. used above or below uncouplingRegrettably,manypeople membranes such as the ARDEX UIinvolved in the installation of tile 740 TM FLEXBONE,highload- productsdontunderstandthat bearinguncouplingmembrane.installed tile moves. If this expect-X4iswaterandfrostresistanted movement is not accommodat-andveryeasytoapplyduetoed, the tile will become rebellious itscreamyconsistency.ARDEXand most likely will become very mortars deliver performance andexpensive for the responsible per-valuefortodaystileinstalla- son or company.tions! For more information, visitIn other words, as a tile installer, it www.ardexamericas.com. is wise to include movement joints oneveryproject. Againhowever, it is not the installers responsibil-itytodesignand/orlocatethese joints. Thatistobedonebythe design professional or engineer.TheattachedTCNAHandbookEJ171detailshowsthenecessary components of the movement joint: Widththatisfourtimesthe expected movement96 TileLetter | July 2020'